The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 24, 1984
Filed:
Dec. 21, 1981
Robert L Hazel, Thousand Oaks, CA (US);
John E Kammerud, Thousand Oaks, CA (US);
Burroughs Corporation, Detroit, MI (US);
Abstract
A method for preformatting each track of an optical disk with spaced header patterns using a plurality of overlapping, individually modulated writing laser beams arranged in a line perpendicular to the track. All of the writing laser beams are derived from a single multi-line laser so as to provide high positioning stability, and adjacent beams are chosen to have different wavelengths in order to prevent the deleterious effects of coherent interference between the overlapping beams. A specific header pattern is provided on a single pass by turning on different ones of the writing beams during specific time periods as each header recording area is traversed. A laser read-after-write beam is additionally provided to permit immediate verification of the recorded header pattern.